This invention relates to a hard armor composite, and more particularly to an improved small arms protection insert (SAPI) applicable for protecting against multiple small arms bullets and projectiles. In a preferred embodiment, the invention incorporates a rigid non-ceramic facing and a ballistic fabric backing.
Ceramic armor is typically used for body armor and for the outer coverings of different types of vehicles, such as various types of land vehicles, ships, and aircraft. Typically, ceramic tiles are adhesively secured to a substrate then encapsulated in an outer cover. The armor system is then attached to a vehicle by a variety of means or merely placed in a fabric pocket, as in the case of body armor. An inherent problem in the prior art is that ceramic armor is relatively heavy, and is configured for a fixed level of protection against a single ballistic threat.
The current SAPI incorporates ceramic and an extended chain polyethylene fiber base material known in the industry as “Spectra Unidirectional Cross Plied”. This material contains fibers produced by Honeywell International, Inc., and distributed under the brand Spectra Shield® PCR and Spectra Shield® Plus PCR. The current SAPI has been accepted for application by the United States military. However, due to limited production and sources of Spectra Shield® PCR and Spectra Shield® Plus PCR, a need exists for an alternative acceptable ballistic fabric construction which can be readily obtained from multiple sources.
A further need exists for a reduced-weight SAPI which offers at least comparable and preferably increased ballistic performance. Military specifications call for a SAPI which meets predetermined maximum weight and performance criteria. The ballistic fabric used in the current SAPI has a denier per filament (dpf) ratio of 5.4—denier being defined as a weight measurement in grams per 9000 meter of fiber length; and denier per filament (dpf) defined as denier divided by the number of filaments in a fiber bundle. For an example, Spectra Shield® PCR comprises a nominal 1300 denier fiber with 240 filaments (or, 5.4 dpf). The present invention uses a lower dpf fiber which meets or exceeds the required ballistic performance criteria. The reduced fiber weight combined with a lighter, less costly non-ceramic facing forms a novel SAPI superior in regards to both weight and performance. The overall weight of the non-ceramic SAPI is well below that prescribed by United States military specifications. In addition, the non-ceramic SAPI is easily molded for enhanced curvature, and has improved field durability as compared to a ceramic SAPI. The ceramic SAPI is extremely hard and brittle, and difficult to shape.